Various proposals have heretofore been made for winding a loop around loop (see, for example, the specification of British Patent No. 329,098).
The British patent discloses a technique for forming a loop around another loop using a knitting needle which has a hook at the needle tip and a plurality of latches.
Theoretically, fabrics can be knitted with use of such needles.
In actuality, however, it was impossible to move the plurality of latches in the order disclosed in the specification of the British patent. Since it was conventionally impossible to control the movement of the plurality of latches, it was impossible to form a fabric wherein loops are provided around other loops.
Accordingly, no fabric is generally available commercially wherein one loop is wound around another loop.
On the other hand, compound needles are known which have a positively controllable latch (see, for example, the specification of U.S. Pat. No. 4,109,490).
The compound needle comprises a shank having a hook at its tip and a guide groove extending longitudinally thereof, and a plate slidably fitted in the guide groove. The hook can be opened or closed by the forward end of the plate by reciprocatingly moving the plate longitudinally thereof.
Nevertheless, a loop can not be drawn around another loop even with use of this compound needle.
To form one loop around another loop, two yarns must be engaged by a single needle at the same time, so that the single needle must be provided with a plurality of hooks or latches, and there arises a need to control the opening and closing of the hooks.